Bulldozer



May 28, 1935. c. JQBATH BULLDOZER I Filed April 8, 1932 2 Sheets-Sheet 1 INK/ENTER- Cm, J .BATH

C. J. BATH May 28, 1935.

BULLDOZER 2 Sheets-Sheet 2 FilezL April 8, 1932 wwwmk m km !I [NI/ENTER cm. J. BA TH. fam mmwm Patented May 28, 1935 r UNITED STATES PATENT OFFICE v r, 7 0 w h V BULLDOZER h I Cyril J. Bath, Shaker Heights, Ohio I Application April 8, 1932, Serial No. 604,000

3 Claims. (01. 153-4 8 The present invention relates to metal working machinesand more particularly to that type of machine known asibenders or bulldozers. These machines are commonly used in machine and job shops for various die operations, and bending and straightening operations on relatively heavy members'such as structural steel, etc.

Machines of the type referred tousually consist of a bed, a die holder or end member on one end of the .bed, a reciprocal ram movable towards and from the end member, and means for reciprocating the ram including a crank mechanism. In operation I the dies are .set up between the" end member andzthe ram by a tedious pack and try method which consists of placing packing behind the dies until they are adjusted to the proper position for the particular job at hand. The maximum capacity or force of the machine is developed only for a short portion of the stroke near the dead center of the crank andwhere a longer maximum power stroke is required to complete a job it'is necessary to stop the machine and fur-" ther pa'ck'the dies, etc., all of which take'sconsid erable time, increasing the set up time required for the job and decreasing the efiiciency andusefulness of the machine.

An object of the present invention is Figure 1 is a perspective view of a bulldozerembodying the present invention, with portions broken away to show certain features, and other features shown diagrammatically.

Fig. 2 is a side elevation of the machine shown in Fig. 1.

Fig. 3 is a plan view of a machine similar to that illustrated in Figs. 1 and 2 but showing anvils in place of die holders, and

Fig. 4 is a side elevation of the machine shown in Fig. 3.

Similar reference characters designate corresponding parts throughout the several figures of the drawings.

Referring to the drawings, the bulldozer illusthe pro-' vision of a novel bulldozer which will be rugged trated is similar in construction to that illustrated and described in my copending application Serial No. 510,401, filed January 22, 1931. a

The frame indicated-in general by the reference character A is preferably of welded plate con struction and has ways I0 and II formed onthe upper side thereof? A housing I2 formed on one end of theframe encloses and supports the main driving mechanism which may be of any conventional construction and forms no part of the pres-. ent invention. i a v A ram I5 provided with a die holder l6 welded or otherwise securedthereto is slidably supported on hardened and groundsteel-wearing plates 13 fixed to the ways l0 and II in any suitable manner., Adjustablegibs carried by the ram l5 and indicated in general bythe reference character M are employed for adjusting the bearings of the ram. The particular construction of the ram so fardescribed forms no part of the present invention and isclearly illustrated in the above mentioned co-pending application. The ram is reciprocated longitudinally of the ways I0 and by means of pitmans l1 and I8, pivotally connected to a shaft '19 supported therein and to cranks on"bull g'ears 2|"and 22 carried on'a shaft 23, at opposite sides of the housing l2. The bull gears are driven from pinions 21 in a well known manner and are provided with a plurality of apertures 28 in which the cranks 20 may be attached. F In operation the load comes on the teeth of "the; bull gears only for 'a-short partof the circumference and the wear is concentrated at this point. By moving the cranks 20 to different positions the wear is distributed about the circumference of the gears thus increasing the life of the same. As illustrated the bull gears 2| and 22 are provided with two apertures 28 spaced 180 apart, thus permitting the cranksZU to be transferred from the positions shown to the other apertures after. one part of the gears has become well worn, but it is understood that more than two apertures may be used, thus still further. increasing the useful life of the bull gears.

An end member built of welded steel plates is slidably supported in the bed or frame A and adjustable towards and from the ram I5 by means of parallel screws 36 and 31 rotatably supported at one end in a cross plate 38. Collars 39 and 40 prevent longitudinal movement of the screws which are threaded at their other ends into elongated nuts 43 positioned in openings in the end member 35 and non-rotatably secured therein by wedge blocks 45. Worm wheels 41 and 48 keyed to the screws 36 and 31 respectively are continuously in mesh with worms 49 and 50 on a shaft 5|. The shaft 5| is rotatably supported in suitable bearings, formed in housings 52 and 53 supported by the screws 36 and 31 etc. enclosing the worm and worm wheels, and is adapted to be rotated in either direction by a reversible electric motor 54 through a flexible drive 55. The motor is preferably controlled from a push button located at any desired place about the machine. From the foregoing description-it will be apparent that the. endemember 35 can be quicklic' and easily adjusted toranw de sired position relative to the ram. The end member 35 carries a die holder 56 either formed inter gral therewith or, as illustrated, detachably secured thereto. A tongue die holder 56 engages in a groove in theend member 35 and assists in holding the parts in their relative positions. 5

In Figs. 3 and 4 the machine is illustrateclas set up for a bending operation. The die'holders' lfi and 56 arereplaced-byanvils Wand M. The

anvils 60 are sliclablysupported by a; member 52 secured to the ram l6 and are? movable towardsand from each other by: a shaft: 63 providedwith right andleft-hand threads: and 65. A: hand wheel 68 is provided=for rotating'the: shaft. 63.:

'I'h'e: anvil-8t has aetapered lowerend Git-which" fitsinto a suitable aperture in the end member 35. The reference chara'ctenW indicates ar work: piece. T-

It will be apparent from the foregoing description that I have providedia machine with a-piurality of novel'featuresr ThemeV-able end'mem ber permits the job-tebe: upin azminirnumtime and the: long screws which takethe thrust of theram have sufficient elasticity or give to prevent breakinglef the-frameetc. when the machine is workedaboveits capacity-.-. This, feature is of considerable advantage because of: the rapidity ,1 with which the-force of theramsincrea-ses ask-the crank approachesdead center, If the dies are: te'o close, even though this distance besmall, machines of this-type aresubieet to tremendeus overload While the: machine illustrated is built:

up of welded-steel plates, itis understood that other constructionsmaybe employed-such as: cast members etc. v

The invention has been described with: refer-- ence to the preferredembcdiment but. it isto. be understood that I-donotwi-shto: belimited tethe particular construction shown asrthe inventionis: capable of being embodied in various construc- 51 on the bottom of the' tions, and this application is intended to cover any and all variations, uses or adaptations thereof as come within knowledge or customary practice in the art to which it pertains, and I particularly point out and claim as my invention:

1. A bulldozer comprising a bed, a slide supported by said bed adjacent one end thereof, a nut carried by said slide, a screw shaft engaging said nut and extending longitudinally of said bed, means adjacentthe end of said-bed remote from said slide for preventinglongitudinal'movement of said screw shaft, a worm wheel keyed to said screw shaft, a shaft supported adjacent said worm wheel, a worm on said shaft engaging said worm wheel} and a reversible electric motor for rotating saidsh-ait.

2. A bulldozer comprising a bed havinga supportingsurface at one end and below the upper surface ofv said bed, a ram reciprocally movable on the upper surface of said bed, means for guiding saidram during its movements, a die supporting member slidably mountedon saidsupportingisms face andhaving screw threaded openings therein, rods screw threaded at one end: for engagement with said screw threaded openings andsecured' at: the-opposite ends against longitudinalmovement: for moving said supporting'member relatively-and independently of said ram, and means for actuating said rods.

bulldozer comprisingv abed. havingram: supporting surfaces and adjacent one end die supporting surfaces located fir-a plane below the. ram supporting surfaces, 2. ram slidably' supported: on saidram supporting surfaces, means connect-- ed to said ramfor reciprocatingthe'latter, a: IIfl]l-- lcwdie supporting" member slidably mounted on: said die supporting surfaces; longitudinally aligned sleevespositioned upon; the oppoate sides of said die supporting. member andsecured :there t0 and internally threaded, rods extending longi tudinally of said bed and having one of theirends screw threaded" for engagement with the; screw threadedsleeves, the opposite-ends of-said rods-bei-- ing-rctatably mounted in said: bed beyondisaid ram, and secured against longitudinal movement with respect to said bed, and means-operatively connected to: the secured ends of said rods-for rotating, the latter inunison whereby-said diesup porting member may be moved independently of. said ram.

CYRIL J i BATH. 

